Polybrush in 2018.2.3

Can't figure out what I'm doing wrong with texture painting. Created a material set the shader to standard texture blend applied it to a plane. GetUsedMeshAttributes is returning an empty array which results in index out of bounds exception.

 

Don't know if this is the same issue, but when I use Polybrush's texture brush, save and shut down, I seem to lose all the texture information and get weird shading(?) when I open Unity back up. I've included an image to highlight the problem. Anybody else getting this or know how to fix it?